How well did each candidate perform in terms of laying out his campaign’s positions and how it differs from his opponent? Which candidate was most effective in laying out his campaign’s mission?

Bill Crotty, a pro­fessor of polit­ical sci­ence and expert in Amer­ican polit­ical par­ties and elec­tions: I had hoped for a cam­paign that would examine the administration’s at best mixed record and offer rea­soned policy options. It is not going to happen.

Vice Pres­i­dent Biden over­whelmed an out­matched Rep. Ryan. Biden is a smart and expe­ri­enced leg­is­lator, the former chair of two major Senate com­mit­tees. He is com­pas­sionate, more artic­u­late than his boss and pas­sion­ately com­mitted to his beliefs. He has been the con­gres­sional liaison and work­horse of the admin­is­tra­tion. It all came into play.

Rep. Ryan is not an espe­cially artic­u­late or com­pelling debater. He was placed in the awk­ward posi­tion of explaining away his votes as a leader of Tea Party Repub­li­cans on Medicare, the budget deficit reduc­tion, jobs, taxes, abor­tion and most every­thing that came up. The gen­er­ality and lack of specifics of the Romney pro­gram may actu­ally have worked to his advan­tage, if any­thing did. These are policy posi­tions with little appeal to a broad public.

Overall, the vice pres­i­dent was most impres­sive. It was his job to make up for the president’s weak showing ear­lier against Romney. He stopped the bleeding — at least until the next pres­i­den­tial debate on Tuesday.

How does Thursday’s debate fit into each campaign’s broader narrative? What did Vice President Biden and Congressman Ryan need to accomplish going into the debate, and to what extent did each man accomplish those goals?

Alan Schroeder, a pro­fessor of jour­nalism and expert in tele­vised debates: The vice pres­i­den­tial debate was of par­tic­ular impor­tance to the Democ­rats because they needed a change of sub­ject after the president’s widely panned per­for­mance in the first debate — and a change of sub­ject is what Joe Biden pro­vided. For the Romney cam­paign there was less at stake. The inter­esting ques­tion on the Repub­lican side was how this debate would affect Paul Ryan’s long-​​range prospects. In my opinion, Ryan came across as not quite ready for prime time; from a career stand­point, how­ever, this rising star of the GOP posi­tioned him­self favor­ably for the future.

In post-​​debate reac­tions Biden is being crit­i­cized for going over the top in his delivery, but all that bluster and laughter and the­atri­cality served a pur­pose: for most of the evening Biden kept his oppo­nent on defense. This debate focused on Mitt Romney’s pro­posals more than Barack Obama’s record, which is exactly what the Democ­rats were hoping for.

What were voters able to learn from each candidate from their behavior and body language? What traits defined each candidate’s performance in the debate?

Greg Goodale, an assis­tant pro­fessor of com­mu­ni­ca­tion studies and expert in body lan­guage and public speaking: Voters should take away from this debate that being aggres­sive is good for democ­racy. Both can­di­dates were impres­sive in their grasp of their party’s ver­sion of the facts. And both men spoke with con­vic­tion as they rebutted each other’s rhetoric.

Not sur­pris­ingly, Vice Pres­i­dent Biden was the star of the debate, though per­haps not in a manner that will win over unde­cided voters. He was bigger-​​than-​​life, often using his hand ges­tures to invade Paul Ryan’s per­sonal space. When lis­tening, his facial expres­sions dis­played a level of dis­dain for his oppo­nent that is likely to leave voters uncom­fort­able. That said, he also came across as com­manding — a problem that Democ­rats had to address because of Pres­i­dent Obama’s poor debate per­for­mance last week. Biden’s mis­sion was to ener­gize the Demo­c­ratic base. He did that.

Ryan’s mis­sion was to appeal to unde­cided voters. And he suc­ceeded too. He was calm and cool in the face of con­tempt and dis­dain. The problem with this strategy, how­ever, is that few unde­cided voters watch vice pres­i­den­tial debates. What the Romney cam­paign aimed to win was the post-​​debate spin. But because Biden came across as bigger-​​than-​​life, the media will focus on the sit­ting vice pres­i­dent. In other words, nei­ther can­di­date will be per­ceived to have won the debate. But those who watched saw a dis­play of policy-​​knowledge and a com­mit­ment to core beliefs that made the audi­ence winners.